This week's rail disaster has train-dependent Japan deeply concerned about safety on the tracks, focusing scrutiny on driver training, carriage design and the ever-present pressure to make the trains run on time.

Monday's wreck would be a shock for any nation. A packed commuter train jumped the tracks in Amagasaki in western Japan and slammed head-on into an apartment complex, killing about 100 people - searchers were still recovering bodies Wednesday - and injuring 450 others.

But the blow has been especially troubling in Japan, which prides itself on an efficient, punctual rail system. Japan's first steam train ran in 1872 as a symbol of the nation's emergence from feudalism, and today 7.2 million people ride on some of the country's 27,516 kilometers of track each day.

``It would worry me to get on a train now,'' said Amagasaki resident Shoko Hirao, 28. ``Until the accident, it had never really occured to me that we would have a major train accident like that - it's frightening.''

Rising suspicions that the train was traveling well over the speed limit have prompted harsh questions about the training of the 23-year-old driver, who overshot the station just before the crash and had only 11 months of experience on the job. Time pressure may have played a key role. The train was 90 seconds behind schedule - a significant delay in a system that, like many things in Japan, is expected to operate with clocklike precision.

JR West issued an internal memo earlier this month telling employees that running late would betray customer trust. The driver of the Amagasaki train - still in the wreckage - is suspected of speeding to make up for lost time.

Doubts have expanded beyond the competence of a single driver. Experts said train advances - such as the automatic brake system being examined in this latest crash - may have made younger drivers less able to manage the train in the event of a technical failure.

Speculation is high that the brake system on that line was an older model and not up to the standards of newer systems - a potential danger for a driver expecting the mechanism to work at the latest levels.

``For the old-timers, having a system like that in place can be of help, but new drivers start out taking it for granted,'' said Kunimichi Takada, a professor at Nihon University. ``In the past, drivers were professionals, like craftsmen. Driving has become easier and drivers trained now are different.''

The operator of the train, West Japan Railway, is also facing tough questions. Dozens of investigators scoured eight of the company's offices Wednesday at the launch of an investigation into possible professional negligence. Some attention has centered on competitive pressures among train companies since the old state-run Japan National Railway was privatized and split up into regional companies in the 1980s.

While the project is often cited by Prime Minister Junichiro Koizumi as successful case of privatization, the accident has raised worries that companies such as JR West have been pushed by competitive pressures to make ever lighter - and quicker - train cars seen as less safe, and adhere to strict timetables. Despite the concerns, train safety has actually increased steadily in Japan.

ASSOCIATED PRESS